Steam-shovel.



strikes against a large portion of the rock and the dipper cannot movefarther rearwardly independently of the rock. When the rock has beenmoved into the clipper as far as possible, the cable 44 is slackened,and the door drops by gravity on to the large protruding portion of therock and is locked 1n this position by the operator or cranemanslackening the line 46 attached to lever -38, thus permitting the pawlsto drop into the ratchet teeth on the rear of the curved hinges 26secured to the regular hinge. Thel rock is thus securely held in thedippe'r and y may be lifted in the usual manner by hoist- 15 in line andtransported, as shown on the le t of Fig. 2, to a car and loweredthereinto. The dipper is lowered thereon until the rock rests on thebottom of the car', and the load is thus taken from the door of thedipper, and in that case the pawls can 'readily be released by suitablvoperating the boom engine, and pulling the line 46 to hold the-pawls outof engagement;

From Fi 1 it will be seen that at a hi her level than t at from which itis remove or -when the car is near the extreme loa'd limit, with theordinary construction of steam shovels it is impracticable to remove andde osit upon a railroad car a rock that is too so arge to pass throughthe steam shovel dip-` per. A rock 53 is shown in the dipper, but

there is no way of depositing the rock upon a railroad car, or at asuicient distance, for' ,f there is no way in which the-rock can bedumped out of thedipper at such' height or at such distance. t

Further advantages of this construction are that, with the oldconstruction, in which the rock enters the top of the clipper, it wasimpossible to determine whether the rock was sufficiently small to passthrough the dipper or not, because the dipper was between the .observerand the rock, while with my present construction it is always easy tosee how to move the dipper rearwardly so as to work the rock into thedipper.

I claim:

In an excavator bucket having a door for closing the bottom'of thebucket and hinged to its back, means to engage the door when the door isswung wide open to hold the same open, means for pressingr material intothe bucket through the bottom while the door is open, means to hold the-door from opening further due to the weight of the material thusreceived in the bucket, and

`means, operable atwill, for releasing said l holding means. l

EUGENE J. MOYNIHAN.

